1. Field
The present embodiments relate to robot drives and, more particularly, to robot drives with magnetic bearings.
2. Brief Description of Related Developments
Conventional robotic drives such as for example, drives for use in a vacuum environment, utilize ball or roller bearings in the vacuum or other controlled environment to support drive shafts of the robotic drive. The bearings supporting the drive shafts may employ various lubricants to prevent metal fatigue and bearing failure. Specially formulate low vapor pressure greases are generally used to lubricate the robot drive bearings in the vacuum or controlled environment.
However, the use of grease to lubricate the robot drive bearings is limited because the lubrication properties of the grease decrease as the vapor pressure and temperature decrease in the robots operating environment. The grease is also a possible source of contamination in a vacuum or other controlled environment due to, for example, outgassing. Further, the greases used in conventional robot drives may break down and can migrate out of the bearings with the potential for contaminating the processing environment and can possibly cause a malfunctioning of the motor feedback systems of the debris from the grease migrates onto the position feedback encoders.
It would be advantageous to have a robot drive system that employs a contactless bearing system, and hence avoiding use of grease or other lubrication of contact surfaces. It would also be advantageous to have a robot drive system that is capable of enhanced mobility without an increase in the number of motors powering the system.